Qualitative analysis: its importance & methods

Analysis is a process or method of determination or estimation or detection or measurement of a substance.

Analysis has two parts one is qualitative aspect and quantitative aspect.

Qualitative aspect is the primary property determined and quantitative is the next one in most determinations.

Qualitative analysis is a quality control for many products emerging out of industry.

This quality is checked by standard institutes like “International Organization for Standardization -ISO”.

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Qualitative analysis:

For instance if a Cop is asking a person to breathe into alcohol breath analyser or meter. The machine first detects if the breathe air contains ethanol in it. If the ethanol is present then it goes for estimating the percentage amount of ethanol in the breathe air.

So in the above instance the identification of ethanol (alcohol) is qualitative aspect. If there is ethanol, then how much of ethanol is present is quantitative aspect. If there is no ethanol (qualitative aspect) then the concept of quantitative analysis doesn’t come into the picture.

Thus qualitative analysis tells what is the substance while quantitative analysis tell how much is the substance.

Qualitative analysis methods:

Quantitative analysis is the direct estimation of component. Hence the methods focuses to estimate the presence of the components.

For example if you take a tooth paste, the components in it can be particles (to polish the teeth), foaming agents (to produce foam and dissolve fatty matter), flavoring agent (to impart good odour), sweetening agent, antiseptic (to kill microbes) etc. So to detect all the components,

we may need

physical methods

chemical methods

Biological methods

Photo-metric methods.

Physical methods in above case of tooth paste can be visual examination of particles, their shape and size by using microscope or magnifying glass. Very rough and large sized particles is not an indicator of quality tooth paste.